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A novel colorimetric-fluorescent dual-mode sensing sensor JT5 was successfully synthesized, and exhibited red fluorescence enhancement effect and red colorimetric sensing, and excellent applicability through solid-state fluorescent strips and biological imaging experiments on zebrafish to highly sensitive monitoring Sn4+ ions. [Display omitted] • A novel and effective rhdamine B-based sensor JT5 successful development. • JT5 can serve as a fluorescent and colorimetric on-off sensor for Sn4+. • The sensor JT5 was successfully studied using fluorescence and colorimetric of the test strips. • Biomaging experiments for the sensor JT5 were conducted on zebrafish using a confocal microscope. A novel colorimetric-fluorescent dual-mode chemosensor (JT5) based on rhodamine B has been produced for monitoring Sn4+ in the DMSO/H 2 O (4:1, v/v) medium. It has high sensitivity, a low detection limit, a short response time (1 s) and high stability, and can still be maintained after two weeks with the red dual fluorescence/ colorimetric response. Enhancement of red fluorescence (591 nm) and red colorimetric (567 nm) response of JT5 by Sn4+ addition. The electrostatic potential of the sensor JT5 molecule was simulated to speculate on the sensing mechanism, and the IR, mass spectrometry and 1H NMR titration were utilized to further demonstrate that JT5 was coordinated to Sn4+ with a 1:1 type, the rhodamine spironolactam ring of JT5 opens up to form a penta-membered ring with Sn4+, meanwhile, its system may have chelation enhanced fluorescence (CHEF) effect. In addition, theoretical calculations were carried out to give the energy gaps of JT5 and [ JT5 + Sn4+] as well as to simulate the electronic properties of the maximal absorption peaks. Notably, the sensor JT5 was successfully applied to monitoring Sn4+ in zebrafish, and the JT5 -loaded filter paper provided a solid-state platform for detecting Sn4+ by both naked eye and fluorescent methods. In summary, this work contributes to monitoring Sn4+ in organisms and solid-state materials and promotes understanding of Sn4+ functions in biological systems, environments, and solid-state materials. [ABSTRACT FROM AUTHOR]

The supramolecular interaction between cucurbit[7]uril (CB[7]) as the host and the anti-cancer drug methotrexate (MTX) as the guest was studied using fluorescence spectroscopy, UV–visible absorption spectroscopy, 1 H NMR, 2D NOESY, and theoretical calculations. The experimental results confirmed the formation of 1:2 inclusion complex with CB[7] and indicated a simple and sensitive competitive method for the fluorescence detection of MTX. It was found that the fluorescence intensities of CB[7]-palmatine, CB[7]-berberine and CB[7]-coptisine were quenched linearly upon the addition of MTX. The linear ranges obtained in the detection of MTX were 0.1–15 μg mL − 1 , 0.2–15 μg mL − 1 , and 0.4–15 μg mL − 1 with detection limits of 0.03 μg mL − 1 , 0.06 μg mL − 1 , and 0.13 μg mL − 1 , respectively. This method can be used for the determination of MTX in biological fluids. These results suggested that cucurbit[7]uril is a promising drug carrier for targeted MTX delivery and monitoring, with improved efficacy and reduced toxicity in normal tissues. [ABSTRACT FROM AUTHOR]

Abstract: Mononuclear and trinuclear Cu(II) complexes with chemical formula [CuL]·CH3OH (1) and [{(Cu(μ-L))2(OAc)2}Cu] (2), where H2L=2,2′-[1,1′-(ethylenedioxydinitrilo)diethylidyne]diphenol, have been synthesized and characterized by elemental analyses, 1H NMR, IR and UV–vis spectra et al. Crystallographic data of complex 1 reveal the formation of an asymmetric mononuclear structure and a slight distortion toward tetrahedral geometry from the square planar structure, in which the introduction of the non-coordinated methanol molecule lead to the assembly of the 1D chains by hydrogen bonding, Cu⋯π and π⋯π interactions. Complex 2 have the elongated square pyramidal geometries for the two terminal Cu(II) ions and an octahedral coordinated geometry for the central Cu(II) ion. In complex 2, two acetate ions coordinate to three Cu(II) ions adopting a familiar syn–syn (μM-O-C-O-M) coordinated fashion. The central Cu(II) ion sits in a crystallographic inversion centre. Therefore, the whole molecule of complex 2 is rigorously centrosymmetric, and forms a 3D supramolecular networks through intermolecular C–H⋯O and C–H⋯π interactions. [Copyright &y& Elsevier]

A novel azine derivative colorimetric and fluorescent dual-channel probe salicylaldehyde hydrazine-3,5-dibromosalicylaldehyde ( 1 ) has been designed, synthesized and characterized. The probe 1 is confirmed to have especial selectivity and good sensitivity on detecting CN − via UV–vis absorption and fluorescence spectrum in aqueous solution (H 2 O/DMSO, 1:4, v/v). This colorimetric and fluorescent dual-channel probe response to CN − owed to the deprotonation process and established the mechanism by using 1 H NMR spectroscopy. Further researches showed that the detection limit of the probe 1 to CN − anions is 8.01 × 10 − 9 M, significantly lower than the maximum level 1.9 × 10 − 6 M in potable water from WHO guidelines. [ABSTRACT FROM AUTHOR]

Highlights: [•] A halogen-substituted Salen-type bisoxime has been synthesized firstly. [•] A new complex [ZnL(H2O)2] n has been synthesized and characterized structurally. [•] The complex forms a self-assembling infinite dual metal–water chain-like structure. [•] Some new results are very important to coordination and supramolecular chemistry. [Copyright &y& Elsevier]

Abstract: Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH3OH)}2(OAc)2Ni]·2CH3OH (I) and [{NiL(C2H5OH)}2(OAc)2Ni]·2C2H5OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5′-di(N,N′-diethylamino)-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H2L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV–vis absorption spectra, TG–DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N2O2 donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures. [Copyright &y& Elsevier]

A novel bis(salamo)-like probe FT was successfully determined, it prescented fluorescent decreased phenomenon for Fe3+ and Cu2+ ions and colorimetric sensing ability towards Cu2+ ions, and excellent applicability were constructed in test filter paper to highly sensitive monitoring Fe3+ and Cu2+ ions. [Display omitted] • A novel and effective bis(salamo)-like probe FT was first successfully developed. • FT uses as a fluorescent ON-OFF probe for Fe3+ and Cu2+ ions. • Theoretical calculations were further applied to explore electronic properties. • FT was employed for monitoring Fe3+ and Cu2+ via test filter paper in real time. A novel bis(salamo)-type sensor FT for fluorescence-colorimetric recognition of Fe3+/Cu2+ has been created, which revealed significant fluorescent performance and colorimetric sensing ability for Cu2+ and Fe3+ ions, superior to other related competitive metal ions. Interestingly, the binding of the FT probe with Cu2+ ions manifested an instant color change from colorless to red in sunlight, which is detectable by the naked-eye, and a fluorescence turn-off response under UV light for Fe3+ and Cu2+. The results demonstrated that the probe exhibits better sensitivity, greater affinity and lower limit of detection leading to quick response time in an aquo-organic medium. The excited state property of the FT probe and in the presence of Cu2+/Fe3+ was evaluated on the basis of DFT & TD-DFT results. Furthermore, test strips have been provided for convenient monitoring of Cu2+ and Fe3+ ions by naked eye and fluorescence method. [ABSTRACT FROM AUTHOR]

Heterotrinuclear 3d–4f complexes with a naphthalenediol-based acyclic bis(salamo)-type ligand have been synthesized and structurally characterized. Spectral titrations clearly show that the heterotrinuclear complexes [Zn 2 (L)La(OAc) 3 ] ( 1 ), [Zn 2 (L)Ce(OAc) 3 ] ( 2 ) and [Zn 2 (L)Dy(OAc) 3 (CH 3 OH)]·CH 2 Cl 2 ( 3 ) are acquired by the substitution reaction of the obtained homotrinuclear Zn(II) complex with 1 equiv. of Ln(NO 3 ) 3 (Ln 3 + = La 3 + , Ce 3 + and Dy 3 + ). Two Zn(II) ions are penta- and hexa-coordinated with geometries of distorted tetragonal pyramid and octahedron. La(III) ion is deca-coordinated, adopting a distorted bicapped square antiprism geometry. Ce(III) ion is nona-coordinated with geometry of distorted capped square antiprism as well as Dy(III) ion. The different coordination modes of acetate ions in complexes 1 , 2 and 3 lead to different coordination numbers of the lanthanide(III) ions. Furthermore, the structures and fluorescence properties have been discussed. [ABSTRACT FROM AUTHOR]

A complexation of non-fluorescent phenformin hydrochloride (PFH) with cucurbit [7]uril (CB [7]) in aqueous solution was investigated using the fluorescent probe of palmatine (PAL) coupled with CB [7]. The fluorescent probe of CB [7]–PAL exhibited strong fluorescence in aqueous solution, which was quenched gradually with the increase of PFH. This effect is observed because when PFH was added to the host–guest system of CB [7]–PAL, PFH and PAL competed to occupy the CB [7] cavity. Portions of the PAL molecule were expelled from the CB [7] cavity owing to the introduction of PFH. Based on the significant quenching of the supramolecular complex fluorescence intensity, a fluorescence method of high sensitivity and selectivity was developed to determine PFH with good precision and accuracy for the first time. The linear range of the method was 0.005–1.9 μg mL − 1 with a detection limit of 0.003 μg mL − 1 . In this work, association constants ( K ) of PFH with CB [7] were also determined. K CB [7]–PFH = (2.52 ± 0.05) × 10 5 L mol − 1 . The ability of PFH to bind with CB [7] is stronger than that of PAL. The results of a density functional theory calculation authenticated that the moiety of PFH was embedded in the hydrophobic cavity of CB [7] tightly, and the nitrogen atom is located in the vicinity of a carbonyl-laced portal in the energy-minimized structure. The molecular modelling of the interaction between PFH and CB [7] was also confirmed by 1 H NMR spectra (Bruker 600 MHz). [ABSTRACT FROM AUTHOR]

Abstract: Amantadine hydrochloride (AMA) and rimantadine hydrochloride (RIM) are non-fluorescent in aqueous solutions. This property makes their determination through direct fluorescent method difficult. The competing reactions and the supramolecular interaction mechanisms between the two drugs and coptisine (COP) as they fight for occupancy of the cucurbit[7]uril (CB[7]) cavity, were studied using spectrofluorimetry, 1H NMR, and molecular modeling calculations. Based on the significant quenching of the supramolecular complex fluorescence intensity, a fluorescent probe method of high sensitivity and selectivity was developed to determine AMA or RIM in their pharmaceutical dosage forms and in urine samples with good precision and accuracy. The linear range of the method was from 0.0040 to 1.0μgmL−1 with a detection limit ranging from 0.0012 to 0.0013μgmL−1. This shows that the proposed method has promising potential for therapeutic monitoring and pharmacokinetics and for clinical application. [Copyright &y& Elsevier]

A new naphthalenediol-based bis(salamo)-type fluorescent probe H 4 L for Zn2+ and CN− was reported. Probe H 4 L showed a highly selective fluorescence enhancement toward Zn2+ over other metal ions including Cd2+, and obtained the L-Zn 2+ complex can only detect CN− in various anions. Their recognition mechanisms were explained by Job plots, fluorescent and UV–vis titrations, and theoretical calculations. The L-Zn 2+ complex has been synthesized and structurally characterized using Hirshfeld surface analysis, elemental analyses, IR, UV–Vis and fluorescent spectra. Additionally, the relay probe with the wide adaptability of pH range and excellent stability showed highly selectivity for CN− recognition. A new naphthalenediol-based bis(salamo)-type fluorescent probe H 4 L was reported, H 4 L showed a highly selective fluorescence enhancement toward Zn2+ over other metal ions including Cd2+, and obtained the L-Zn 2+ complex can only detect CN− in various anions. Unlabelled Image • A highly selective and sensitive fluorescent probe H 4 L for Zn2+ and CN− was synthesized. • The L-Zn 2+ complex has been synthesized and characterized structurally. • Recognition mechanism for Zn2+ was supported by theoretical calculations. [ABSTRACT FROM AUTHOR]